The DE25-15B450 combines hi-fi sound with the high efficiency of a PA loudspeaker.
To achieve this we:
- used one of the most linear tweeters, the B&C DE 25
please refer to K&T 3/98:...inside tip...
- fitted a perfectly matched bass driver, the Oberton 15 B450
- developed a crossover according to hi-fi specs
- designed the crossover in such a way that it copes easily with the high power.
The crossover frequency is 2.1 kHz with 18 dB / octave to avoid an overdriven
tweeter, while the phase response remains in tact.

The 60 litre bass reflex speaker has a high efficiency of 99 dB, a power handling
of 450/900 Watts (continuous/peak) and a frequency response of 50 - 18.000 Hz
(with a fluctuation of only +/- 1.5 dB between 70 - 17.000 Hz).

The frequency response is measured at the tweeter's lower edge, in 2, 4 or 8
metres distance. Please enquire for additional data should the listening position
be considerably lower or higher.

Building instruction (60 litre cabinet)

The napped foam should be fitted to the upper half of the rear wall, behind
the DE25 and the bass driver.

Building instruction for reduced height:
If you prefer a lower cabinet the two bass reflex tubes may be replaced
by a 22 x 6 cm duct with a depth of 10 cm. Therefore, the horn needs to
be moved 6 cm to the side.

Two wooden panels are needed, one with 22 x 8 cm, one with 9.8 x 8cm.

This reduces the height by 14 cm, while the depth is increased by 3.4
cm, ensuring the same volume.